Printer has failed its first service

First for delivery: Fast shipping
Delivery: Unfortunately Online was not described that the delivery includes a USB cable. Instead buy recommendation from AMAZON (Value USB cable USB 2.0 A / B m / m 300cm order together). Bin this recommendation followed -> out waste of money. Fortunately only 3.42.
Unpacking and start according to instructions carried out (see, inter alia Tonerkatuschen and shaking), so far everything was fast and easy.
Startup: error message "imaging unit is not installed". In the manual found nothing about it. As I suspected that the PHD was meant I have taken Tonerkatuschen, mount Tonerkatuschen expanded (all very easy), now removed imaging drum (also surprisingly easy). PHD replaced correctly and paid to engage. Everything reinstalled. Switched on and .... error message "imaging unit is not installed". All In.- and expansion steps are repeated and re-assembled. But in addition moves the contacts of the imaging drum and cleaned with a handkerchief (below the contacts of the cartridge behind the front cover). Turned on the printer and .... he ran. I hope that this error has occurred due to transport and does not repeat itself.
Now running the printer and provides a good printed image, but only up to max. 160gr paper.